1. Field of the Invention
The present invention pertains to methods of treating hyperbilirubinemia and pharmaceutical and/or dietary preparations for such treatment. Specifically, the present invention pertains to a method of treating hyperbilirubinemia with an oral preparation in which chitosan is the active agent.
2. Description of the Prior Art
Hyperbilirubinemia is a condition of mammals, specifically humans, in which there are excessive amounts of bilirubin in the blood. Bilirubin is the chief pigment in human bile. It is derived from hemoglobin which is the red pigment of the red corpuscles. The main site of bilirubin is the liver. It is also made in the bone marrow, the spleen and the lymph glands.
Free bilirubin is the most toxic substance produced by the human body. In normal adults, however, the bilirubin is conjugated in the liver, i.e. converted to a nontoxic form known as bilirubin-glucuronide. Conjugation of bilirubin in the liver is catalyzed by the enzyme UDP-glucuronyl transferase. The conjugated form of bilirubin is water-soluble and can be excreted into the bile. While bile is passed into the intestines and the gall bladder, part of the bilirubin is converted into sterco-bilin and excreted in the feces. The remainder is reabsorbed in the bloodstream and of this portion the bulk returns to the liver to be reexcreted into the bile.
Hyperbilirubinemia frequently occurs in the first five days of life of a newborn baby and may clear up within seven to fourteen days. This condition known as "physiological jaundice of newborns" or "neonatal jaundice" is due to incomplete development of certain mechanisms of the body resulting in a decreased ability to conjugate bilirubin with glucronic acid. Specifically, the key enzyme, UDP-glucuronyl transferase, is not present in the newborn, requiring several weeks to be fully induced. As a result, the bilirubin cannot be conjugated and is retained in the body for some time. The condition is usually mild and self-limiting, though in premature infants, the hyperbilirubinemia may be more severe, last longer, and more frequently result in kernicterus. Kernicterus may result in severe neurological deficits, mental retardation, loss of IQ and even death.
It is estimated that as many as twenty-five percent of newborns are afflicted with this malady. In adults, hyperbilirubinemia, commonly referred to as "Gilbert's Disease", frequently results in death.
Neonatal jaundice has been successfully treated by complete blood transfusion, administration of phenobarbital and total body irradiation by visible light (phototherapy). Blood transfusion is quite inconvenient for babies. The most popular treatment is phototherapy. While phototherapy is effective, it is thought to be destructive of certain other body functions and perhaps harmful to a degree not known at the present time. Specifically, phototherapy has come under recent attack because of possible damage through photodynamic action possibly caused by bilirubin and its numerous photo-oxidation products.